Abstract. The genera Cochleariella and Hilliella are reduced to synonymy of Yinshania, a genus considered to be endemic to China. The following new combinations are proposed: Yinshania acutangula ssp. microcarpa, Y. acutangula ssp. wilsonii, Y. yixianensis, Y. rivulorum, Y. sinuata, Y. sinuata ssp. qianwuensis, Y. lichuanensis, Y. rupicola, Y. rupicola ssp. shuangpaiensis, and Y. hunanensis. Descriptions and distributions are provided, and keys to the species and subspecies are given.

There has been considerable controversy with regard to the generic identity of some of the Chinese-endemic Brassicaceae (Cruciferae) that were originally placed by Schulz (1923, 1929, 1936) in Cochlearia L. sect. Hilliella O. E. Schulz. The number of taxa recognized varied between 10 and 25 species in one to four genera. A compilation of the work of Zhang (1985, 1986, 1987a, 1987b, 1996a, 1997) and Zhang and Cai (1989) shows that the 25 species and five varieties recognized in this complex were assigned to the genera Cochleariella Y. H. Zhang & R. Vogt(1 species), Hilliella (O. E. Schulz) Y. H. Zhang & H. W. Li (16 species), and Yinshania Ma & Y. Z. Zhao (9 species), whereas Ying et al. (1993) accepted 1 species in Cochleariella, 13 in Hilliella, and 9 in Yinshania. By contrast, Kuan (1987) placed 13 species in Cochlearia, Lu (1991, 1993) treated 9 in Cochlearia and 1 in Cochleariopsis Y. H. Zhang (=Cochleariella), and Zhao (1992) recognized 14 species in Yinshania and 1 in Cochlearia. The lack of agreement among these authors and the need to treat the complex for the forthcoming account of the Brassicaceae for the Flora of China necessitated a critical evaluation of the taxa to determine the number of genera and species involved. As shown below, the endemic Chinese plants of this complex of four genera (Cochlearia, Cochleariella, Hilliella, and Yinshania) belong to one genus hereafter called Yinshania.

COCHLEARIA

A critical comparison of the Chinese Yinshania with the Eurasian and North American Cochlearia reveals that the genera have very little in common. Species of Cochlearia are distributed in the arctic, subarctic, and northern latitudes of the northern temperate region, and they most commonly grow in coastal habitats, mountain streamsides, sandy beaches, seashore rock crevices, gravel bars, alpine habitats, saltmarshes, saline meadows, and calcareous screes (Pobedimova 1969, 1970; Rollins, 1993; Jackson and Akeroyd, 1993). Cochlearia consists of usually glabrous and glaucous small plants with ± fleshy, simple, entire to dentate leaves, erect petals and stamens, inflated but somewhat angustiseptate (flattened at a right angle to the septum) fruits, prominently 1-veined valves, often biseriate tuberculate seeds, and accumbent or rarely incumbent cotyledons. In contrast, Yinshania is endemic to China, and the plants grow from near sea level to 1,600(--3,000) m on mountain slopes, rocky crevices, shady moist areas, dense forests, roadsides, streamsides, shady river banks, limestone areas, and wet valleys. Yinshania differs from Cochlearia in being robust, usually pubescent plants, with nonfleshy, pinnatisect or trifoliolate to pinnately compound leaves (Y. sinuata has large simple or rarely trifoliolate leaves), widely spreading sepals, petals, and stamens, terete to latiseptate (flattened parallel to septum) or rarely slightly angustiseptate fruits, inconspicuously veined valves, uniseriate or rarely biseriate and reticulate or sometimes papillate seeds, and incumbent or rarely accumbent cotyledons.

COCHLEARIELLA

The monotypic Cochleariella Y. H. Zhang & R. Vogt was originally described as Cochleariopsis Y. H. Zhang (Zhang, 1985; Zhang and Cai, 1989), a later homonym of Cochleariopsis of Löve and Löve (1976). It rests primarily on the presence of coarse, inflated, thin-walled papillae on the fruit valves, as compared with their absence in species of Yinshania. The density of papillae varies within and among populations and ranges from being abundant to sparse or completely lacking. Plants exhibiting the various extremes of this variation were described as independent taxa. For example, those with fruit valves densely covered with large papillae are recognized as C.zhejiangensis (Y. H. Zhang) Y. H. Zhang & R. Vogt, whereas those with glabrous fruit valves are called Y. warburgii (O. E. Schulz) Y. Z. Zhao, and plants with sparse, slender valve papillae are treated as Y. fumarioides (Dunn) Y. Z. Zhao. Fruits of the Y. warburgii holotype are immature, but they show a clear similarity to immature fruits of C. zhejiangensis and Y. fumarioides in the developmental stages of papillae. The types of these three "species" are basically indistinguishable in other morphological characters. Lu (1993) was correct in reducing C. zhejiangensis to synonymy of Y. warburgii, but she maintained the species in Cochleariopsis and did not associate it with Y. fumarioides. In our opinion, Cochleariella does not merit recognition.

HILLIELLA

Cochlearia L. sect. Hilliella was raised to the generic rank by Zhang and Li (Zhang, 1986), and it was said to differ from Yinshania in having compound instead of pinnatisect leaves, simple instead of forked trichomes, eseptate instead of septate fruits, and papillate instead of reticulate seeds. Only 2 of the 11 Yinshania species recognized by Zhang (1996a) have branched trichomes, and reticulate seeds occur in both Hilliella and Yinshania (Zhang, 1996a; Zhao, 1991). As for the presence versus absence of septa, this feature is not useful at the generic rank, and septate and eseptate fruits occur within numerous genera of the Brassicaceae. Some of the species described or maintained by Zhang (1986, 1987b) in Hilliella have fruits with complete septa. Finally, both compound and pinnatisect leaves are found within Yinshania, and as delimited by Zhang (1986), Hilliella included species with simple or compound leaves. The genus Cardamine L. includes species with simple, pinnatisect, trifoliolate, or pinnately compound leaves. As shown by Al-Shehbaz and Yang (1998), two of the eight species recognized in Hilliella by Zhang (1986) are members of the genus Cardamine. We fully agree with Zhao (1992) and Lu (1991) that the alleged differences between Hilliella and Yinshania are inconsistent and that a single genus should be recognized.

YINSHANIA

As delimited here, Yinshania consists of 13 species and four subspecies. The genus is endemic to China and is distributed in 17 of the 28 provinces and autonomous regions of China. These include Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Hubei, Hunan, Jiangxi, Nei Mongol, Shaanxi, Sichuan, Taiwan, Xizang, Yunnan, and Zhejiang.

INFRAGENERIC CLASSIFICATION OF YINSHANIA

Zhang (1987a) divided Yinshania (excluding Hillliella, which she recognized as a distinct genus), into two sections solely on the basis of differences in fruit shape. Section Microcarpa Y. H. Zhang was characterized by having subglobose to broadly ovoid fruits 1.0--2.2 mm long, whereas sect. Yinshania was said to have oblong-ovoid, oblong, to lanceolate-ellipsoid fruits 1.5--4.5 mm long. However, these alleged differences represent continuous variation, and they do not justify the division of the genus into sections. As shown below, in Y. acutangula and Y. zayuensis, fruit shape sometimes varies on the same plant, depending on the number of ovules that mature into seeds. Zhang (1987a) divided sect. Yinshania into two series: ser. Henryanae Y. H. Zhang (infructescence rachis flexuous, trichomes simple or branched, dense, leaves 3- to 5-foliolate or pinnatisect to pinnatipartite) and ser. Yinshania (infructescence rachis straight, trichomes simple or branched, sparse or absent, leaves pinnatisect to pinnatipartite). We believe that these differences are also unreliable, and in Y. zayuensis the infructescence rachis can be straight or flexuous.

Zhao (1992) maintained Y.sinuata as a species of Cochlearia and divided Yinshania into two sections: sect. Yinshania (leaves pinnatisect or pinnatipartite) and sect. Hilliella (leaves all or lowermost compound). He followed Zhang (1987a) in using fruit shape to divide sect. Yinshania into ser. Microcapae and ser. Yinshaniae. Zhao divided sect. Hilliella into four series on the basis of differences in leaflet shape and the presence versus absence or type of trichomes. However, these subdivisions are artificial, and his monotypic series Alatipes included a species of Cardamine (see Al-Shehbaz and Yang, 1998).

In our opinion, the infrageneric subdivisions above are neither practical nor useful, and they do not reflect the phylogenetic relationships in Yinshania. Unless the infrageneric subdivisions meet these criteria, there is no need for them in the Brassicaceae, especially in small genera.

From the other members of Yinshania, Y. acutangula is readily distinguished by having angled stems with subappressed, simple straight trichomes, ebracteate inflorescences with straight rachis, and pinnate leaves with leaflets less than 1 cm wide. It is quite variable in the degree of development of stem angles, size of leaf divisions, density of flowers on the inflorescence branches, fruit shape and indumentum, and number of seeds per locule. The variation, however, is rather continuous, and only the following three subspecies can be consistently recognized on the basis of the characters in the key below.

Zhao (1992) has correctly recognized Y. wenxianensis and Y. acutangula as conspecific, but he wrongly adopted the much-later-published Y. albiflora for the combined species.

The alleged differences listed by Zhang (1987a) to distinguish between the two varieties of Y.wenxianensis (i.e., distribution and density of indumentum, infructescence length, and trichomes length) show a great deal of overlap, and the distinction is unrealistic. Furthermore, the slight differences in fruit length and seed number between the two varieties of Y.wenxianensis on the one hand and var. acutangula on the other are unreliable, and therefore they are reduced here to synonymy of var. acutangula.

The presence of pilose instead of minutely papillose fruits in this subspecies is significant and might justify its recognition as an independent species. However, all other characters of the plant readily fall within the variation range of Y. acutangula ssp. wilsonii, and glabrous and pubescent fruits are found in other species, such as Y. henryi. Both Zhang (1987a) and Zhao (1992) recognize Y. microcarpa as a species distinct from Y. acutangula, whereas Lu (1991) did not include it in her account. In fact, Zhang (1987a) placed Y. acutangula and Y. microcarpa in independent sections separated mainly on the basis of differences in fruit shape.

Although Schulz (1935) cited two collections (Wilson 3210 and Wilson 3210a) in his original description of C. henryi var. wilsonii, the single specimen at BM (Wilson 3210), which Schulz cited and which is annotated in Schulz's handwriting, should be considered the type. Furthermore, Schulz gave detailed descriptions of the fruit and seeds that were observed in Wilson 3210. Plants of Wilson 3210a have flower buds and no fruits.

It is difficult to understand why Schulz (1935) described this taxon as a variety of C. henryi (here Yinshania) instead of his C. acutangula. Yinshania henryi is readily distinguished from the three subspecies of Y. acutangula in having distinctly flexuous infructescence axes and canescent leaves densely with trichomes (0.5--)0.6--1.0 mm long, whereas Y. acutangula has straight infructescence axes and green leaves glabrous or sparsely with trichomes (0.1--)0.3--0.4(--0.5) mm long.

The presence of short (vs. long) inflorescence branches is the sole feature that distinguishes var. barchybotrys from var. qianningensis. The type collection of var. wilsonii above includes both inflorescence types. The degree of elongation of the lateral inflorescence branches does not appear to be taxonomically useful.

Zhao (1992) recognized Y. qianningensis as an independent species, but the overall morphology clearly supports the recognition of a single taxon here treated as ssp. acutangula.

Distribution: Anhui. Known only from the type collection, which was grown from seeds.

Although we have not seen the type of this interesting species, the detailed protologue and photograph clearly support its close relationship to Y. acutangula. Zhang (1995a) compared and associated Y.yixianensis (as Hilliella)with H. paradoxa, but the latter has trifoliolate instead of pinnate leaves. The flexuous lateral branches of the inflorescence of Y.yixianensis are a remarkable feature that readily distinguishes it from most species of the genus. Except for the unrelated Y.henryi and Y. furcatipilosa, both of which have canescent leaves, conspicuously flexuous infrutescences are not found elsewhere in the genus.

Although we have been unable to examine the types of Y. exiensis and Y. ganluoensis, the descriptions and illustration provided by Zhang (1987a, 1993, 1996a) clearly show that these "species" are indistinguishable from Y. zayuensis. The presence of minutely puberulent furcate trichomes on the leaves and stems is not found in any other species of Yinshania. The three "species" are very similar in all other characters, except for slight differences in fruit shape. Zhang (1993) placed Y. zayuensis and Y. ganluoensis in two different sections of Yinshania primarily on the basis of fruit shape (subglobose to broadly ovoid in sect. Microcarpa vs. ovoid to oblong in sect. Yinshania). However, it is abundantly clear from the morphology of the two plants that they are conspecific and that the division of the genus into sections on the basis of slight differences in fruit shape is unwarranted.

Yinshania zayuensis was misidentified and illustrated in Flora Reipublicae Popularis Sinicae (An, 1987) as Camelina yunnanensis W. W. Smith, but as indicated below, the latter is a synonym of Rorippa globosa (Turczaninow) Thellung.

One collection, Forrest 13955, was listed as Sisymbriumsonnei Robinson (Notes Roy. Bot. Gard. Edinburgh 17: 31. 1929), and the label carries the name Mekongiayunnanensis W. W. Smith. However, neither of these two names has been validly published.

Fruit indumentum is the most variable feature in Y. fumarioides, and this variation was the principal reason for recognizing three species variously placed in one to four genera. As shown above, Cochleariella is indistinguishable from Yinshania in every feature, and Zhao (1992) was the first to point that out. However, he recognized Y. fumarioides, Y. warburgii, and Y. zhejiangensis as independent species. Lu (1993), on the other hand, was the first to reduce the last species to synonymy of Y. warburgii, but she maintained Cochleariella as independent from the remaining species that she placed in Cochlearia. Furthermore, Lu (1991) retained Y. fumarioides in Cochlearia. By contrast, Zhang (1995b) maintained Y. zhejiangensis in the monotypic Cochleariella, and she recognized Y. warburgii and Y. fumarioides in Hilliella (1987a, 1995b). The failure of these authors to associate Y. warburgii and Y. zhejiangensis with the earlier-published Y. fumarioides probably resulted from a failure to examine the type material of the last species.

In his original description of Nasturtium henryi, Oliver (1887) cited a single collection (Henry 2899) and indicated that "this singular plant, which for the present may be left in Nasturtium, may prove ultimately better disposed of in Lepidineae as a distinct generic type." Another collection (Henry 4125, see below), which was made in 1888 presumably from the same general area of the type locality, has been wrongly annotated by various botanists as a syntype, but this collection was not cited in the original publication and therefore has nothing to do with the type collection. It is interesting that Oliver's suggestion that N. henryi belongs to a distinct genus was overlooked until Ma and Zhao (1979) described Yinshania more than a century later.

Lu (1991) did not recognize Y. henryi nor list it in the synonymy of any species. The species can easily be distinguished from other members of Yinshania in having canescent, deeply crenate leaves with simple trichomes (0.5--)0.6--1.0 mm long and flexuous infructescences.

Yinshania henryi is most closely related to Y. furcatipilosa, which it resembles in having flexuous infructescences, canescent leaves, and long trichomes ca. 1 mm long. The latter has bifurcate trichomes, whereas Y. henryi has simple ones. The differences in leaf shape and petal length listed by Ying et al. (1993) to distinguish between Y.henryi and Y.fumarioides are unreliable, and both species have mostly ovate leaflets and petals over 3 mm long.

This is the most distinctive species of the genus because of its canescent leaves densely covered with bifurcate trichomes 0.25--0.5(--0.6) mm long and its distinctly flexuous inflorescences. It is most closely related to Y.henryi, from which it is readily distinguished in having furcate instead of simple trichomes.

Yinshania rivulorum is the only species of the genus that extends outside mainland China into Taiwan, where it is known as Cochlearia formosana. Zhao (1992) confused the nomenclature of the species and reduced it (as C. rivulorum) to synonymy of the later published Y. formosana (see the synonymy above).

Zhang(1986) recognized three varieties of Hilliella alatipes, each of which clearly represents a distinct species. As shown by Al-Shehbaz and Yang (1998), two of these varieties belong to two remarkably different species of Cardamine, and Cochlearia (or Hilliella) alatipes is a synonym of Cardaminefragariifolia O. E. Schulz. The third of Zhang's varieties, var. micrantha, is definitely a synonym of Y. rivulorum, a species also recognized by Zhang (1986). Zhao (1992) treated all of Zhang's three varieties of H. alatipes, along with Y. lichuanensis, as synonyms of Y. alatipes. Yinshania lichuanensis is a very distinct species that differs from Y. rivulorum (here including only one of Zhang's three varieties of H. alatipes) in being puberulent plants with acuminate-caudate leaf apices and fruit appressed to rachis. In contrast, Y. rivulorum has usually glabrous plants with obtuse to acute leaf apices and widely spreading to reflexed fruit.

Yinshaniarivulorum appears to be very rare in Fujian and Hunan, as evidenced from the few type collections above. It is much more widespread in Taiwan. The type of H.alatipes var. micrantha differs from the rest of the collections here treated as Y.rivulorum in having slightly longer (6.0 vs. 3.0--4.5 mm) fruits and acute instead of obtuse or subacute leaf apex. Because only the type of var. micrantha has been examined, it is unclear whether or not this variety deserves recognition.

In superficial examination, Y. sinuata looks very much like some forms of Eutrema. However, the two genera are unrelated. Yinshania species have predominantly compound or deeply pinnatifid basal leaves not deeply cordate basally; nontorulose fruits; spreading sepals, petals, and stamens; and petals about the same size as sepals and not differentiated into a claw and blade. In contrast, Eutrema always has simple basal leaves with cordate base, predominantly torulose fruits, erect floral parts, and petals distinctly longer than sepals and always differentiated into blade and claw. In our opinion, Yinshania appears to be more closely related to Cardamine than to Eutrema.

The original publication gave Dai 150 as the holotype, but the type in PE bears Dai 159. All of the other information given in the original publication matches Dai 159, and there is no Brassicaceae specimen at PE that bears Dai 150. Therefore, we believe that the collection number in the original publication was a typographical error.

Both subspecies of Y. sinuata are poorly collected, and the apparently sufficient differences between the two may not remain with the gathering of more extensive material. Zhao (1992) reduced this subspecies to synonymy of Y. rivulorum (as Y. formosana), but it is evident that the two belong to different species. Yinshania rivulorum is characterized by having all stem leaves trifoliolate, petals 1.5--2.5 mm long, anthers ca. 0.2 mm long, and oblong papillate fruits 6--12 x 1.7--2.3 mm. In contrast, Y. sinuata has all leaves simple or only the lowermost trifoliate, and the petals are 0.8--1.1 mm, anthers 0.45--0.55 mm, and ovate glabrous fruits 4--6 x ca. 1.5 mm.

According to Zhang (1986), the type of ssp. qianwuensis was collected on 8 May 1958 at 700 m. The other collection of this taxon (Hu 1701), which was annotated by Zhang as the isotype, was collected on 6 May 1958 at 200 m and therefore does not belong to the type collection.

An examination of a large number of specimens of this complex reveals that H. lichuanensis, H. longistyla, H. guangdongensis, and H. changhuaensis are conspecific. Zhang (1987b) separated these primarily on the basis of differences in the density of indumentum on the inflorescence, length of style, and size and shape of the fruit. However, all of these characters show continuous variation, and it is impossible to subdivide this complex into distinct entities. Zhang (1987b) separated H. lichuanensis from the other three species above primarily on the basis of its having hairy versus glabrous sepals and inflorescence. When used alone in the Brassicaceae, the density or even presence versus absence of indumentum often are among the most unreliable features for recognizing taxa. Zhang separated H. longistyla from the other three species on the basis of its having long styles ca. 1 mm in flower and ca. 2 mm in fruit. However, the other three species (H. lichuanensis, H. guangdongensis, and H. changhuaensis) were said to have styles 1.0--1.5 mm long. Zhao (1992) was the first to correctly place these four species under one name, but he wrongly listed them as synonyms of Y. alatipes, a species clearly shown by Al-Shehbaz and Yang (1998) to be the same as Cardamine fragariifolia. In the absence of mature fruits, Cardamine can be easily separated from Yinshania because of its having erect rather than spreading petals and stamens and a broad rather than narrow placental region. Three of Zhang's (1987b) species of Hilliella(H. lichuanensis, H. changhuaensis, and H. longistyla), along with Y. alatipes, were recognized as distinct species of Cochlearia by Lu (1991), but as indicated above, these Chinese species are unrelated to Cochlearia.

The original description of Cochlearia rupicola indicated that the plant is annual, but the illustration and the isotype above clearly show that the plant is perennial. Subspecies rupicola is only known from the type collection, and nothing can be said about its overall variability. It is remarkably similar to ssp. shuangpaiensis in all other morphological characters, including leaf shape, flower size, rhizomes, lack of septum, length of style, flattening of fruit, and presence of a short gynophore, and the only basic difference between the two is the fruit shape and size given in the key above. Therefore, it is more practical to treat the two taxa under the same species.

The strongly recurved, slender fruiting pedicels, the flattened suborbicular fruit, and oblong-lanceolate, trifoliolate, uppermost stem leaves are quite characteristic of this subspecies. Although we have not examined the holotype, the excellent illustration and detailed description of H. xiangguiensis clearly show that the taxon is indistinguishable from the plants treated here as ssp. shuangpaiensis.

Zhao (1992) reduced Y. hunanensis to synonymy of Y. huii. Although we have not seen material of the latter, the protologue shows that it is quite different from Y. hunanensis, and the two species can be readily separated by characters listed under Y. huii.

Habitat and phenology: Known only from two syntypes above. Both are flowering material collected in April at 1500 m.

Distribution: Jiangxi.

Yinshania huii is most closely related to Y. hunanensis, and they are easily separated from the remaining species of Yinshania on the basis of their bracteate inflorescences. The syntypes of Y. huii have not been seen. From the original description, C. huii is an annual, with narrowly cylindric pistils, 8-ovuled locules, and papillate fruit valves. Yinshania hunanesis is a perennial, with ovate pistils, 1- or 2-ovuled locules, and glabrous fruit valves. Yinshania huii was recognized by Lu (1991) as Cochlearia, but its relationship to Y. hunanensis was not indicated, and the latter species was not mentioned

We are grateful to Paul Berry for his critical review of the manuscript. We thank Henry Noltie for his help in providing information about some collections at the Royal Botanic Garden, Edinburgh. We thank the directors and curators of A, B, BM, E, GH, HAST, IBSC, K, KUN, LE, MO, NAS, NY, P, PE, TAI, TI, TNS, US, W, and WU for allowing our study of the cited specimens.